Component 52: Selective Splitter (Filter)

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Component 52: Selective Splitter (Filter)

Specifications

Line connections
1	Inlet
2	Outlet
3	Branching with mass flows of the selected components

General User Input Values Physics Used Displays Example

General

Component 52 enables the separation of the material flows of a fluid (gaseous, liquid or solid). The following can be modelled, for instance, with this component:

Gas cleaning
Cyclones
Venturi washer

The proportionate extraction of a material X is described by the specification value JX, whereby X is the short name of the material. The materials that can be extracted depend upon the fluid type. See the chapter on Pipe Overview for more details.

Alternatively, the composition of the separated fluid can be specified externally (by a component 33, start value). In this case, it is required that the substances that have to be withdrawn are available in the inlet flow in sufficient quantities.

This component allows a transition between different material tables, even with different zero points for the enthalpy. A transition to the 2-phase material library is possible for the fluids LibNH3, LibCO2 and Water. For user-defined fluids, it is not possible.

Example for the application: separation of CO2 from the flue gas with liquidizing afterwards

Note the behaviour of this component when you separate fluids with phase transitions: when you separate only one phase, component 52 separates as much from this fluid as corresponds of the specified phase at the inlet of component 52. Nevertheless, at the outlets of the components, there will be a new phase equilibrium of both phases according to the thermodynamical quantities and the partial pressures in the outlet pipes.

To facilitate the modeling of chemical processes, the modes FM = 4 and FM = 5 have been implemented to allow to define the ratio of the substances at the outlet. Here the specification values J.. are not interpreted as separation rates but as the relative ratio of the substances among each other that is to be achieved on the outlet line. At FM = 4, the mass fractions are specified here, and at FM = 5 the molar fractions.

The separation quantity is defined by the specification value RR (reaction rate). For RR = 1, as much as possible is separated, i.e. so much that nothing is left of (at least) one substance.

Model

The total mass flow of line 3 results from the junction rates Ji (0<=Ji<=1, i stands for the components) and the weight parts X1i=M1i/M1 of line 1

M3= S[X1i * Ji] * M1

The portion at the line 3 is calculated analog to

X3i = X1i * Ji * M1/M3

The relations for mass flow and the components at line 2 result in

M2= S[X1i * (1-Ji)] * M1

X2i = X1i * { 1-Ji } * M1/M2

The pressure is assumed to be constant

If FSPECH=0, then (T1 is specified)

T3=T1, T2 from energy balance

If FSPECH=1, then (T2 is specified)

T1=T2, T3 from energy balance

If FSPECH=2, then (T1 is specified)

T3=T2=T1, without taking into account the energy balance

The enthalpies result from the total of the specific enthalpies Hi at the temperatures and the components Xi result in

H2= S[Hii * X2i]

H3= S[Hii * X3i]

Similar components:

Component 4 (simple branching):

The branching mass flow 3 must be specified (e.g. through the component 33, pastille) or else it must be known in the system by other means.

Component 17 (branching with characteristic line):

The branching mass flow 3 must be specified via a characteristic line, which specifies the branching behaviour depending upon the incoming mass flow.

Component 18 (branching with default specification of the branching ratio):

The branching mass flow 3 is specified as a portion in the incoming mass flow. This relation does not change for the off-design mode.

Component 19 (drying of wet steam):

The extracted wetness results from the specification of the portion, by which the available wetness in the wet steam is to be reduced.

Component 54 (drying of gaseous fluids):

This component determines, whether water is present in air, flue gas, fuel gas, coal or crude gas as a result of the partial pressures. It can be defined, which portion of the available wetness is to be reduced.

User Input Values

FM	Mass flow distribution =2: M1 or M3 given =3: M1 or M2 given =4: M3 calculated by reaction rate RR and Jxx as mass ratios =5: M3 calculated by reaction rate RR and Jxx as molar ratios =-1: M3 and composition given from outside. In this case, the composition of the separation is not determined by the Jxxx, but is specified from the outside (on line at connection 3). The Jxxx are therefore blanked out and ignored. At the inlet, mass flow and composition must be given in any case. The mass flow must be large enough for separation to be possible.
RR	Used with FM=4 or FM=5 only: Reaction rate
FSPECH	Handling of energy balance =0: T3=T1, T2 from energy balance =1: T1=T2, T3 from energy balance =2: T3=T2=T1, without taking the energy balance into account - The result value DQ will not be 0. =-1: All temperatures given externally - without taking the energy balance into account - The result value DQ will not be 0. Note: under normal circumstances outlet temperatures will be equal for all streams. But in case different thermal property sets are used for different outlet streams, or real gas properties are used, an enthalpy change can occur. The energy balance difference caused by the setting that all streams are at equal temperature is reported as result variable DQ.
FADAPT	Flag for using the adaptation polynomial ADAPT/ adaptation function EADAPT =0: Not used and not evaluated =1: Factor of all Jxx (i.e. all separation rates are multiplied with the same factor) =1000: Not used, but ADAPT evaluated as RADAPT (Reduction of the computing time) = -1: EADAPT Factor of all Jxx (i.e. all separation rates are multiplied with the same factor) = -2: EADAPT interpreted as separation rate directl - values < 0.00 and values > 1.00 will be cut off to 0 and 1 resp.. To allow to specify different separation rates for the individual substances, the KE_Internal-Variable subst_id has to be used when programming the Kernel expression. The component evaluates the Kernel expression in a loop for each substance existing on the inlet line and, in doing so, hands over the substance currently under consideration in subst_id. See example below. = -1000: Not used, but EADAPT evaluated as RADAPT (Reduction of the computing time)
EADAPT	Adaptation Function
JN2	N2 fraction
JO2	O2 fraction
JCO2	CO2 fraction
JH20G	Water fraction (gaseous)
JH20L	Water fraction (liquid)
JSO2	SO2 fraction
JAR	Argon fraction
JCO	CO fraction
JCOS	COS fraction
JH2	H2 fraction
JH2S	H2S fraction
JCH4	CH4 fraction
JHCL	HCL fraction
JETH	Ethane fraction
JPROP	Propane fraction
JBUT	n-Butane fraction
JPENT	n-Pentane fraction
JHEX	n-Hexane fraction
JHEPT	n-Heptane fraction
JACET	Acetylene fraction
JBENZ	Benzene fraction
JC	C fraction
JH	H fraction
JO	O fraction
JN	N fraction
JS	S fraction
JCL	CI fraction
JASH	Ash fraction (not gaseous)
JASHG	Ash fraction (gaseous)
JLIME	Lime (Ca(OH)2) fraction
JCA	Elemental calcium fraction
JH2OB	chemically bonded water fraction (Water in fuel)
JNO	NO-fraction
JNO2	NO2-fraction
JNH3G	fraction of gaseous NH3
JNH3L	fraction of liquid NH3
JMG	Elemental magnesium (Mg) fraction
JMETHL	fraction Methanol
JCACO3	CaCO3 fraction
JCAO	CaO-fraction
JCASO4	CaSO4-fraction
JMGCO3	MgCO3-fraction
JMGO	MgO fraction
JOCT	n-Octane fraction
JNON	n-Nonane fraction
JDEC	n-Decane fraction
JDODEC	n-Dodecane fraction
JIBUT	Isobutane (2-Methylpropane) fraction
JIPENT	Isopentane (2-Methylbutane) fraction
JNEOPENT	Neopentane (2,2-Dimethylpropane) fraction
J22DMBUT	Neohexane (2,2-Dimethylbutane) fraction
J23DMBUT	2,3-Dimethylbutane fraction
JCYCPENT	Cyclopentane fraction
JIHEX	Isohexane (2-methylpentane) fraction
J3MPENT	3-Methylpentane fraction
JMCYCPENT	Methylcyclopentane fraction
JCYCHEX	Cyclohexane fraction
JMCYCHEX	Methylcyclohexane fraction
JECYCPENT	Ethylcyclopentane fraction
JECYCHEX	Ethylcyclohexane fraction
JTOLUEN	Toluene (toluol, methylbenzene) fraction
JEBENZ	Ethylbenzene fraction
JOXYLEN	ortho-Xylene (1,2-dimethylbenzene) fraction
JCDECALIN	cis-Decalin (decahydronaphthalene) fraction
JTDECALIN	trans-Decalin (Decahydronaphthalene) fraction
JETHEN	Ethene (ethylene) fraction
JPROPEN	Propene (propylene) fraction
J1BUTEN	1-Butene fraction
JC2BUTEN	cis-2-Butene fraction
JT2BUTEN	trans-2-Butene fraction
JIBUTEN	Isobutene (2-Methylpropene) fraction
J1PENTEN	1-Pentene fraction
JPROPADIEN	Propadiene (allene) fraction
J12BUTADIEN	1,2-Butadiene (methylallene) fraction
J13BUTADIEN	1,3-Butadiene (vinylethylene) fraction
JETHL	Ethanol fraction
JCH3SH	CH3SH (methanethiol, methylmercaptan) fraction
JHCN	Hydrogen cyanide (prussic acid) fraction
JCS2	Carbon disulfide fraction
JAIR	Air fraction
JHE	Helium fraction
JNE	Neon fraction
JKR	Krypton-fraction
JXE	Xenon-fraction
JN20	Dinitrogen monoxide (laughing gas) fraction
JCO2L	CO2 (liquid)-fraction
JH2OL	Water (liquid)-fraction
JNH3L	NH3 (liquid) fraction
DTMAX	Maximum permissible temperature deviation (taking into account the energy balance)

Input: 0<=Ji<=1 , i stands for the components

Generally, all inputs that are visible are required. But, often default values are provided.

For more information on colour of the input fields and their descriptions see Edit Component\Specification values

For more information on design vs. off-design and nominal values see General\Accept Nominal values

Physics Used

Equations

All cases

p2 = p1 (1)

p3 = p1 (2)

M3i= X1i *Ji*M1

M3 = S(M3i) (5)

X3i = X1i * Ji * M1/M3

M2 = M1 - M3 (6)

X2i = X1i * { 1-Ji } * M1/M2

X3i from the mass balance

H2 = S [ Hi * X2i ] (3)

H3 = S [ Hi * X3i ] (4)

FADAPT = 0: ADAPT Not used and not evaluated

FADAPT = 1 : ADAPT = Factor of all Jxx (i.e. all separation rates are multiplied with the same factor)

FADAPT = 1000 : Not used, but ADAPT evaluated as RADAPT (Reduction of the computing time)

FADAPT = -1: EADAPT = Factor of all Jxx (i.e. all separation rates are multiplied with the same factor)

FADAPT = -2: EADAPT = Separation rate for all Jxx (With the use of subst_id, all separation rates can be different)

FADAPT = -1000 : Not used, but EADAPT evaluated as RADAPT (Reduction of the computing time)

Example for a Kernel-Expression with FADAPT=-2

If, for instance, you want to separate half of the water and all of the CO2 and all of the SO2, you can use the following EADAPT-code:

function evalexpr:REAL;

var val:real;
       internals:array of InternalValue;
       n:integer;
       i:integer;
       subst_id:integer;

begin
       internals := keGetInternals();
       n := length( internals );
       if (n > 0) then subst_id :=internals[0].value;

       if (subst_id = 4) then begin // H2O
         val:=0.5;
       end else if (subst_id = 3 or subst_id = 5) then begin // CO2 und SO2
         val:=1.0;
       end else begin
         val:=0.0;
       end;
       evalexpr := val;
end;

Component Displays

Display Option 1

Example

Click here >> Component 52 Demo << to load an example.